What Types of Aquarium Fish Are the Most Aggressive?

All complex living organisms have attitudes, some more than others, and this extends to the species that are suitable for fish keeping. How much of a positive or negative attitude fish will display depends on their genetic and evolutionary traits as well as environmental factors. Unlike mammals, fish aren’t guided by emotions or rationalizations, yet they can still react to some situations with aggression under certain circumstances. Setting aside survival instincts, some fish tend to be more aggressive than others because such has been the determination of Mother Nature. The staff at Aquatic Warehouse, a trusted aquarium supplier, has put together a list featuring a few of the most aggressive species that can be reasonably kept in aquariums, although some of them will require special care.

Piranhas

By virtue of being tropical fish, piranhas can be raised and kept in aquarium tanks, but the only species suitable for keeping would be the colorful Pygocentrus nattereri because it can stunt its growth to about 20 centimeters in length. Piranhas are voracious scavengers and extremely messy eaters. Their aggression comes out when they feed, and they’ll become predators and even cannibals if the situation arises. The only reason to keep red piranhas is because they’re exotic or if the future owner is nuts. They’re illegal in most states.

Oscar Fish

The color spots on the scales of this fish are reminiscent of tiger patterns. For some reason, Oscars don’t get along with other fish or even invertebrates very well, but of course there are exceptions to the rule. They’re not even that good at fighting, but they can become problematic if they grow larger. Since Oscar fish come in different colors and won’t fight each other, it’s fine to keep a tank stocked with nothing but Oscars. This goes for most of the larger South American cichlids.

Rainbow Sharks

Similar to other Asian tropical species, Epalzeorhynchos frenatum are extremely territorial, and they’ll act as bullies toward all other smaller species that dwell on or near the bottom. Thankfully, rainbow sharks don’t grow very large. However, it’s better to keep only one when you have a smaller tank. Breeding this species will require too much patience. Curiously, rainbow sharks won’t bother rainbowfish or danios even when they’re about the same size.

Siamese Fighting Fish

Since the 19th century, these extremely territorial fish have been bred specifically for fighting. In Thailand, even the Royal Family was involved in the breeding and keeping of Betta splendens for licensed fights that featured heavy wagering. Fighting fish are simply fascinating in terms of watching their courtship rituals and territorial fighting. Although males are more attractive and colorful, females have been known to fight each other. Bottom feeders can be cohabitants of tanks with bettas, but they need to be of a similar size.

Tiger Barbs

Unlike Siamese fighting fish, tiger barbs get along with members of their own species. In fact, they’ll swim in schools, and this is the only way to keep them unless they’re the only species in the tank. A solitary tiger barb will bite, bully, and bother other aquarium mates incessantly. In some cases, larger fish will get tired of the harassment and attack the tiger barb.

No matter what type of fish you choose to keep, you’ll need several supplies to properly maintain your aquarium. Whether you need a dosing pump, protein skimmer, filtration system, heater, or any other essential supplies, you can find what you’re looking for at Aquatic Warehouse. Stop by our store in Kearny Mesa, take a look at our website to see what we have to offer, and give us a call at 858-467-9297 if you have any questions.